Fragment to small molecule hit discovery targeting Mycobacterium tuberculosis FtsZ

针对结核分枝杆菌 FtsZ 的小分子片段发现

• 批准号: MR/Z503757/1
• 负责人: Geoffrey Wells
• 金额: $ 17.72万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FZ503757%2F1
• 关键词: Fragment; small; molecule; hit; discovery

Tuberculosis (TB) is a major cause of morbidity and mortality in developing and developed countries. 10.6 million people developed the disease and 1.6 million people died from TB in 2021. Approximately 450,000 reported cases are classified as multidrug-resistant tuberculosis (MDR-TB), with a subset of patients developing extensively-drug-resistant tuberculosis (XDR-TB).About a quarter of the world's population have latent TB, with ~10-15% going on to develop and spread the infection. Patient access to current treatments, and compliance with the lengthy dosing regimens is a global challenge. MDR-TB is more difficult to treat, and options for the emerging XDR-TB are even more limited. There is an urgent unmet medical need to develop novel anti-TB agents to successfully combat emerging resistance. Recent progress has been achieved by the repurposing and redosing of known anti-TB drugs, but there are no new drug classes in clinical trials that act by novel mechanisms of action.The protein "Filamenting temperature-sensitive mutant Z" (FtsZ) is highly conserved among all types of bacteria, including Mycobacterium species that cause TB. It is an essential cell division protein with both GTPase and polymerisation activities. FtsZ subunits polymerise into protofilaments to form a dynamic ring-like structure called the Z-ring that functions as a scaffold for the assembly of the divisome, a multiprotein complex that causes contraction of the Z-ring, finally resulting in septum formation and cell division. Abnormalities in FtsZ block the Z-ring functions, leading to an elongated, filamentous phenotype, inhibition of cell division and subsequent cell death. Although FtsZ inhibitors have been identified, most are derived from natural products and there is a general lack of structural information, with many of the inhibitors classified as "false positives".We have purified M. tuberculosis (MTb) FtsZ in large amounts for biochemical, biophysical and structural studies. In collaboration with the Monash NMR screening facility, we identified 38 fragment hits against FtsZ. We established biophysical (DSF, MST) and biochemical (GTPase, right-angle scattering) assays to characterise its GTPase activity and polymerisation/depolymerisation dynamics. Uniquely, we have determined the crystal structure of FtsZ in complex with fragment hits and established their mechanism of action. We have evaluated the fragment binding sites with respect to fragment growth and merging and we are ready to initiate SAR-by-catalogue and custom-made optimisation of the hits to develop more potent analogues.In this project we aim to develop and characterise potent inhibitors of MTb FtsZ as a new class of antibiotic for the treatment of tuberculosis infections. We anticipate that such compounds will be a welcome addition to the treatment options available for TB and its drug-resistant variants. This collaborative drug discovery project addresses a clear unmet medical need. Successful completion of this project will underpin a broader collaborative drug discovery program including other UCL partners.

结核病（TB）是发展中国家和发达国家发病率和死亡率的主要原因。 2021年，有1,160万人出现这种疾病，有160万人死于结核病。报告的病例被归类为多药耐药性结核病（MDR-TB），其中一部分患者发展为抗药性的结核病（XDR-TB）（XDR-TB）。如果世界人群的四分之一均与〜10-15％的销量相关。患者获得当前治疗，并且遵守长期给药方案是一个全球挑战。 MDR-TB更难治疗，新兴XDR-TB的选择更加有限。紧急未满足的医疗需求是开发新型的抗TB剂以成功地打击新兴的耐药性。通过重新利用和释放已知抗TB药物的重新利用和释放已经实现了最近的进展，但是在临床试验中没有新的药物类别通过新型作用机理起作用。蛋白质“丝离素对温度敏感的突变Z”（FTSZ）在所有类型的细菌中都高度保守，包括引起TB的分枝杆菌。它是具有GTPase和聚合活性的必不可少的细胞分裂蛋白。 FTSZ亚基聚合到原丝中，形成一种动态环状结构，称为Z形环，该结构是divisome组装的脚手架，这是一种多蛋白络合物，这是一种导致Z环收缩的多蛋白络合物，最终导致隔膜形成和细胞分裂。 FTSZ的异常阻止了Z环的功能，导致延长的丝状表型，对细胞分裂的抑制以及随后的细胞死亡。尽管已经鉴定出FTSZ抑制剂，但大多数均来自天然产物，并且通常缺乏结构信息，许多抑制剂被归类为“假阳性”。我们已经纯化了结核分枝杆菌（MTB）FTSZ的生物化学，生物物理学，生物物理和结构研究。通过与Monash NMR筛查设施合作，我们确定了38个针对FTSZ的片段。我们建立了生物物理（DSF，MST）和生化（GTPase，右角散射）测定法，以表征其GTPase活性和聚合/去聚合动态。独特的是，我们已经确定了与碎片命中的复杂性中FTSZ的晶体结构，并确定了它们的作用机理。我们已经评估了有关碎片生长和合并的片段结合位点，我们准备启动sar-catalogue和量身定制的命中优化，以开发更有效的类似物。在这个项目中，我们旨在开发和表征MTB FTSZ的有效抑制剂，以治疗抗生素的新类别，用于治疗结核病的新型抗生素。我们预计，此类化合物将是TB及其耐药性变体的治疗选择的可喜补充。这个协作的药物发现项目解决了明确的未满足的医疗需求。该项目的成功完成将支持包括其他UCL合作伙伴在内的更广泛的协作药物发现计划。